Electric circuit test element for use with a pair of electrical connectors

ABSTRACT

A pair of harness connectors have sandwiched between them a test connector or element which carries on its external cylindrical surface a number of test circuit terminals, one for each pin in the test element. The leads between the test circuit terminals and the test element pins, as well as the terminals themselves, may be printed circuits. A meter is tapped onto any given test circuit terminal and is provided with a probe so it can be grounded. The test element is divided into two or three discs so it can accommodate a greater number of circuits to be tested.

United States Patent 1 Arlow 1 Feb. 27, 1973 Michael S. Arlow, Livonia,Mich.

The United States of America as represented by the Secretary 01 the ArmyFiled: Feb. 1, 1971 Appl. No.: 111,296

Inventor:

Assignee:

References Cited UNITED STATES PATENTS 4/1951 McNabb ..324/51 Lilli kid;I II Conrad ..324/23 X 3,340,491 9/1967 Deakin ..339/194 R 2,448,4528/1948 Morelock ..324/158 F 2,732,533 1/1956 Andrews et a1. ..339/l56 TPrimary Examiner-Gerard R. Strecker Attorney-Harry M. Saragovitz, EdwardJ. Kelly, l-lerbert Berl and John F. Schmidt [5 7 ABSTRACT A pair ofharness connectors have sandwiched between them a test connector orelement which carries on its external cylindrical surface a number oftest circuit terminals, one for each pin in the test element. The leadsbetween the test circuit terminals and the test element pins, as well asthe terminals themselves, may be printed circuits. A meter is tappedonto any given test circuit terminal and is provided with a probe so itcan be grounded. The test element is divided into two or three discs soit can accommodate a greater number of circuits to be tested.

5 Claims, 7 Drawing Figures PATENTEB FEB 2 7 I973 SHEET 10F 3 M/CHAEL 5.ARLOW //VVg/)\ /TOR H M. Saragov/fz, E J. Kelly h. Ber/ 8 John F SchmidtATTORNEYS ELECTRIC CIRCUIT TEST ELEMENT FOR USE WITH A PAIR OFELECTRICAL CONNECTORS BACKGROUND OF THE INVENTION 1. Field of theInvention This invention relates to devices to test electric circuits,and especially electronic circuits, while the connected electric orelectronic device is in operation.

2. Description of the Prior Art There are many closed loop electroniccircuits in industrial applications and in mobile equipment, such asmilitary equipment, for which qualification, test, and check-outprocedures are highly desirable and, in case of failure, actuallynecessary. The troubleshooting of electronic circuits can be greatlysimplified and expedited if they can be monitored while in operation.Moreover, in many applications, a wiring harness transmits power both toand from a so called black box. Disconnecting such a harness for test orcheck purposes interrupts a closed loop circuit and thus disrupts unitoperation. Ideally, all units should be tested under dynamic rather thanstatic conditions, and this is not usually possible with conventionaltroubleshooting methods and equipment, which require lengthy, indirectand expensive routines.

SUMMARY OF THE INVENTION The invention is a test element which is usedwith the two connectors of a pair of connectors in an electric circuit,usually in a wiring harness for an electronic device. The test elementis series compatible with the pair of harness connectors for which it isdesigned, and consists of a support carrying a plurality of contactsextending through the support and adapted on each face of the support toengage electrically the corresponding terminals of the two connectors ofsaid pair, which in many cases will mean that one end of a contact inthe support will be a plug and the other end a socket to engagerespectively a socket terminal and a plug terminal in the connectors ofthe pair with which the test element is used.

THE DRAWINGS FIG. 1 is a plan view, with parts broken away and insection, of a pair of conventional connectors with which the inventionis to be used.

FIG. 2 is a view in elevation, with parts broken away and in section, ofan electric circuit test element made according to this invention.

FIG. 3 is a view in elevation of a pair of connectors of a wiringharness, shown assembled with a test element embodying this invention.

FIG. 4 is a view substantially on line 4-4 of FIG. 2.

FIG. 5 is a view substantially on line 5-5 of FIG. 2.

FIG. 6 is a view substantially on line 66 of FIG. 2.

FIG. 7 is a schematic view of a wiring harness circuit showing anapplication of a' test element made according to this invention.

Referring now more specifically to the drawings and in greater detail,FIG. 1 shows a pair of connectors 2 and 4 of a conventional type. In theembodiment here shown, connector 2 is provided with a plurality ofsocket terminals 6 which make electrical contact with plug terminals 8in connector 4.

Cooperable with the connectors 2 and 4 is a test element 10 made inaccordance with the invention. The embodiment here shown provides athree-part support 12 fora plurality of contacts 14. Support 12comprises a plurality, here shown as three, of discs 12a, 12b and 120.Each contact 14 passes through or traverses all of the discs in order toprovide means electrically to engage the terminals of connectorsadjacent its two faces. Because connectors 2 and 4 here shown areprovided with socket and plug terminals 6 and 8 respectively, each ofcontacts 14 correspondingly comprises a plug portion 16 and a socketportion 18.

Making support 12 in more than one part makes it possible to concentratea larger number of contacts in one test element without interferencebetween the several terminals and their leads to an external testcircuit terminal. As can be seen from a consideration of FIGS. 4, 5 and6, the test element here shown carries 36 contacts for engagement withthe 36 terminals of connectors 2 and 4. Each contact 14 must be providedwith a test circuit terminal and must be electrically connected with itsterminal. Thus, a test circuit terminal 20 is provided for each contact14, being connected by a suitable lead 22, the test circuit terminalsand leads being here shown as 20a, 20b, 20c and 22a, 22b, 220 for discs12a, 12b, 12c respectively. If all 36 electrical connecting means, orleads, 22a, 22b, and 220 had to be placed on one surface, they wouldinterfere to the extent of leakage from one contact to another, arcingacross, or simply shorting across because of insut'ficient space. Theproblem is substantially averted by distributing the leads on threesurfaces as shown in FIGS. 4, 5 and 6.

Test circuit terminals 20 are placed so as to be readily accessible whentest element 10 is assembled with a pair of connectors as in FIG. 3. Inthe configuration of the illustrated embodiment of the invention, theexternal or accessible surface, with the connectors and the test elementassembled, available to hold the test circuit terminals 20 is thecylindrical surface of the threepart element 10 which appears in FIG. 3.

In a preferred embodiment of the invention, test circuit terminals 20and leads 22 can take the form of printed circuits suitably connected,as by soldering, with their respective contacts 14. Terminals 20 can benumbered or otherwise marked with distinguishing indicia foridentification, by means of a tabularcode or key, with the associatedcircuit. The connectors and the test element may be suitably polarizedso as to be assemblable in only the desired orientation, with the resultthat any given test circuit terminal in the test element is alwaysconnected with the same circuit when the test element is plugged intothe harness for which it is designed.

OPERATION Reference is now made to FIG. 7 for a discussion in detail ofthe application of a test element made according to this invention. Anysuitable power source 24, here shown as a battery, is connected with aharness having a cable 26 to which connector 2 is electrically joined.Between connectors 2 and 4, the test element 10 is disposed, beingplugged into both connectors as in FIG. 3. A cable 28 is electricallyjoined with connector 4 and may if desired include one or more switchessuch as the one shown at 30. An electronic device 32 is shown connectedin the harness. Device 32 would account for at least one of the circuitsof the harness and could of course be of such a nature as to beconnected with all of the circuits in the harness. In many cases, device32 will be grounded as shown at 34.

An instrument lead 36 is shown connected with test element 10. As willbe understood by those skilled in the art, lead 36 will contact theappropriate test circuit terminal as determined by the indicia and thetabular key to enable an operator to plug into whatever circuit is to betested. A multimeter 38 is shown as being connected with lead 36 and asgrounded at 40, the ground 40 here being shown schematically as providedby suitable conventional test probe 42.

I wish it to be understood that I do not desire to be limited to theexact details of construction shown and described, for obviousmodifications will occur to a person skilled in the art.

What is claimed is:

l. A test element for use with a pair of electrical connectors havingplug and socket terminals, the element comprising a nonconductivesupport composed of a plurality of discs, a plurality of electricallyconductive elongated one piece integral metal contacts held by thesupport and each of which has a plug portion and a socket portionwherein the two portions are coaxial and are cooperable with a socketterminal and a plug terminal respectively of said pair, a test circuitterminal for each of said contacts on said support and accessible fromoutside the assembled pair and support, and

means electrically connecting each test circuit terminal with a contact,each disc carrying a proportionate share of test circuit terminals onits periphery and a corresponding proportionate share of said electricalconnecting means.

2. A test element for use with a pair of electrical connectors, eachconnector carrying a plurality of terminals adapted to make electricalcontact with the terminals of the other connector and the two connectorsbeing engageable and disengageable to make and break respectively saidelectrical contact between terminals, the invention comprising anonconductive support positionable between the two connectors and composed of a plurality of discs, a plurality of elongated electricallyconductive one piece integral metal contacts held by said support, eachcontact having a plug adapted to engage a terminal in one connector andhaving coaxial with the plug a socket which in transverse section isintegral and receives the corresponding terminal in the other connectorto establish an electric circuit between said two terminals when saidsupport is positioned between and in engagement with said twoconnectors, a test circuit terminal for each of said contacts, the testcircuit terminals mounted on said support and accessible from outsidethe assembled connectors and support, and means electrically connectingeach test circuit terminal with a contact.

3. A test element as in claim 2, wherein the socket portion of each ofsaid contacts is supported by each of said plurality of discs.

4. A test element for use with a pair of electrical connectors, eachconnector carrying a plurality of terminals adapted to make electricalcontact with the terminals of the other connector and the two connectorsbeing engageable and disengageable to make and break respectively saidelectrical contact between terminals, the invention comprising anonconductive support positionable between and in engagement with saidtwo connectors, and when in such engagement having an exposed surface,the support composed of a plurality of discs, a plurality of elongatedelectrically conductive one piece integral metal contacts held by thesupport, each contact passing through the support and having a plugadapted to engage a terminal in one connector and having coaxial withthe plug a socket which in transverse section is integral and receivesthe corresponding terminal in the other connector to establish anelectric circuit between said two terminals when the support is betweenand in engagement with the two connectors, a test circuit terminal foreach of said contacts, said test circuit terminals mounted on saidexposed surface of said support, and means electrically connecting eachtest circuit terminal with a contact.

5. A test element as in claim 4, wherein the socket portion of 'each ofsaid contacts is supported by each of said plurality of discs.

1. A test element for use with a pair of electrical connectors havingplug and socket terminals, the element comprising a nonconductivesupport composed of a plurality of discs, a plurality of electricallyconductive elongated one piece integral metal contacts held by thesupport and each of which has a plug portion and a socket portionwherein the two portions are coaxial and are cooperable with a socketterminal and a plug terminal respectively of said pair, a test circuitterminal for each of said contacts on said support and accessible fromoutside the assembled pair and support, and means electricallyconnecting each test circuit terminal with a contact, each disc carryinga proportionate share of test circuit terminals on its periphery and acorresponding proportionate share of said electrical connecting means.2. A test element for use with a pair of electrical connectors, eachconnector carrying a plurality of terminals adapted to make electricalcontact with the terminals of the other connector and the two connectorsbeing engageable and disengageable to make and break respectively saidelectrical contact between terminals, the invention comprising anonconductive support positionable between the two connectors andcomposed of a plurality of discs, a plurality of elongated electricallyconductive one piece integral metal contacts held by said support, eachcontact having a plug adapted to engage a terminal in one connector andhaving coaxial with the plug a socket which in transverse section isintegral and receives the corresponding terminal in the other connectorto establish an electric circuit between said two terminals when saidsupport is positioned between and in engagement with said twoconnectors, a test circuit terminal for each of said contacts, the testcircuit terminals mounted on said support and accessible from outsidethe assembled connectors and support, and means electrically connectingeach test circuit terminal with a contact.
 3. A test element as in claim2, wherein the socket portion of each of said contacts is supported byeach of said plurality of discs.
 4. A test element for use with a pairof electrical connectors, each connector carrying a plurality ofterminals adapted to make electrical contact with the terminals of theother connector and the two connectors being engageable anddisengageable to make and break respectively said electrical contactbetween terminals, the invention comprising a nonconductive supportpositionable between and in engagement with said two connectors, andwhen in such engagement having an exposed surface, the support composedof a plurality of discs, a plurality of elongated electricallyconductive one piece integral metal contacts held by the support, eachcontact passing through the support and having a plug adapted to engagea terminal in one connector and having coaxial with the plug a socketwhich in transverse section is integral and receives the correspondingterminal in the other connector to establish an electric circuit betweensaid two terminals when the support is between and in engagement withthe two connectors, a test circuit terminal for each of said contacts,said test circuit terminals mounted on said exposed surface of saidsupport, and means eleCtrically connecting each test circuit terminalwith a contact.
 5. A test element as in claim 4, wherein the socketportion of each of said contacts is supported by each of said pluralityof discs.